Controlling apparatus for highway crossing signals



Aug. 3, 1937. G. R. PFLASTERER 2,088,758

- CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNALS Filed Oct. 50, 1936 [TR ZYP'U 5TH l NTOR fiil H15 ATTORNEY Patented Aug. 3, 1937 UNITED STATES PATENT OFFIQE CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNALS Application October 30, 1936, Serial No. 108,430

12 Claims.

My invention relates to controlling apparatus for highway crossing signals, that is, to apparatus for the control of signals which are placed at the intersections of railways and highways for the purpose of warning users of the highway when a train is approaching.

One object of my invention is the provision of means for causing the signal to give the warning until the rear end of a train has completely cleared the highway.

The apparatus set forth in the present applica tion is somewhat similar to that set forth in the prior copending application, Serial No. 66,255, filed February 28, 1936, for Railway track circuit apparatus, by Robert M. Gilson, and the said copending application contains claims which cover broadly certain features of the invention described in the present application.

I will describe one form of apparatus embodying my invention, and will then. point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view illustrating one form of apparatus embodying my invention.

Referring to the drawing, the reference characters 4 and 5 designate. the rails of a stretch of railway track over which traffic moves in both directions. The rails of the stretch are divided by insulated joints 6 into two relatively long end sections IT and 3T which are separated from each other by a relatively short intermediate section 2T. The section 2T includes an intersection by a highway H. The intersection is protected by a signal S of any suitable type such, for example, as a bell or a light signal or a combination of both. For controlling the signal, an interlocking relay K is provided having a magnet MI and a magnet M3. For controlling the interlocking relay magnets MI and M3, a series track circuit including the rails of the stretch is provided.

As hereshown, this track circuit includes track relays I'I'R and 3TB connected across the rails at the extreme ends of the stretch, track relay 2TB, connected across insulated joint 6 at the left of the intersection, and a track battery I connected across the insulated joint 6 at the right of the. intersection. It will be apparent that relays ITR, 2TH and 3TR will become released whenever sections IT, ZT and 3T, respectively, are occupied by a train.

Magnet MI is provided with a circuit which includes front contact 8 of relay ITR and front contact 9 of relay 2TB, and magnet M3 is provided. with a circuit which includes front .con-

tact ID of relay 3TB. and front contact II of relay 2TB. That is, magnet MI will become released Whenever either relay I'I'R, or ZTR is released, and magnet M3 will become released whenever either relay 3TB or ZTR is released.

Assuming that an eastbound train, that is, a train traveling from left to right, enters section IT to release relay ITR, it will be clear that the opening of front contact 8 of relay ITR will cause magnet MI to become released so that back contact I2 of magnet MI will become closed to cause operation of signal S. When the train occupies section 2T, the releasing of relay 2TB. will, of course, cause magnet MI to remain released so that the signal will continue to operate as long as section 2T is occupied. When the train enters section 3T, the interlocking feature of the relay K will prevent the closing of back contact I3 of magnet M3 so that the signal cannot operate after the train vacates section 2T and magnet MI again becomes energized to open contact I2.

The signal S is also provided with an operating circuit which includes back contact Id of relay 2TB. so that the signal S will be certain to operate as long as any portion of a train occupies the intersection regardless of the condition of the interlocking relay K.

The operation of the apparatus for a westbound train has not been described because it will be understood that such operation will be similar to that just described for an eastbound train.

Although I have. herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

' Having thus described my invention, What I claim is:

1. In combination, a stretch of railway track insulated at each extreme end from the adjoining track and including an intersection with a highway, an insulated joint in one rail of said stretch adjacent one side of said intersection and another insulated joint in the other rail of said stretch adjacent the other side of said intersection, a source of energy connected across said one insulated joint, three track relays one connected across the rails at each extreme end of said stretch and one connected across said other insulated joint, and a highway crossing signal at said intersection controlled by said three relays.

2. In combination, a stretch of railway track insulated at each extreme end from the adjoining track and including an intersection with a highway, an insulated joint in one rail of said stretch adjacent one side of said intersection and another insulated joint in the other rail of said stretch adjacent the other side of said intersection, a source of energy connected across said one insulated joint, three track relays one connected across the rails at each extreme end of 10 said stretch and one connected across said other insulated joint, directional. means controlled by said three relays, and a highway-crossing signal at said intersection controlled by said means.

3. In combination, a stretch of railway track 15 insulated at each extreme end from the adjoining track and including an intersectionwith ahighway, an insulated joint in one rail of said stretch adjacent one side of said intersection and another insulated joint in the other rail of said stretch adjacent the other side of said intersection, a source of energy connected across said one insulated joint, three track relays one connected across the rails at each extreme end of said stretch and one connected across said other insulated joint, an interlocking relay controlled by said three relays, and a highway crossing signal at said intersection controlled by said interlocking relay.

91. In combination, a'stretch of railway track 30 insulated at each extreme end from the adjoining track and including an intersection with a highway, an insulated joint in one rail of said stretch adjacent one side of said intersection and another insulated joint in the other rail of said 3 stretch adjacent the other side of said intersection, a source of energy connected across said one insulated joint, three track relays one connected across the rails at each extreme end of 7 said stretch and one connected acrosssaid other 40 insulated joint, a highway crossing signal at said intersection, an interlocking relay including a first magnet and a second magnet for governing said signal, a circuit for said first magnet including a frontcontact of the track relay connected .45 across the rails at one end of the stretch as Well as a front contact of the track relay connected across said insulated joint, and a circuit for said second magnet including a front contact of the track relay connected across the rail at the other end of the stretch as well as a front contact of the track relay connected across said insulated joint.

i In combination, a stretch of railway track insulated at each extreme end from the adjoin- 55 ing track and including an intersection with a highway, an insulated joint in one. rail of said stretch adjacent one side of said intersection and another insulated joint in the other rail of said stretch adjacent the other side of said intersection, a source of energy connected across said one insulated joint, three track relays one connected across the rails at each extreme end of said stretch 'and one connected across said' other insulated joint, an interlocking relay governed by said 65 three relays, a highway crossing signal at said intersection, and circuits for said signal governed by said interlocking relay as well as by a 1 76 side'of said intersection whereby said stretch is divided into two end sections and an intermediate section; a series track circuit including a track battery connected across said one insulated joint, a track relay connected across the other insulated joint and two other track relays, one connected across the rails at each extreme end of 'said stretch; a highway crossingsignal at said intersection, and means governed by said three track relays for governing said signal whereby the signal will be caused to operate only when a train is approaching the intersection in the two end sections but will be caused to operate for a train moving in either direction in the intermediate section.

'7. In combination, a stretch of railway track including an intersection with a highway; a track circuit for said stretch including two relays, one connected across the'rails at opposite ends of the stretch, and including a source of energy connected in series with one rail as well as another track relay connected in series with the other 'rail, said source of energy and said other track relay being located on. opposite sides of said intersection, and means governed by saidthree relays for governing a highway crossing signal at said intersection. v

8. In combination, a stretch of railway track including an intersection with a highway, a track circuit including twotrack relays one connected across the rails at each end of said stretch, a

source of track circuit energy connected in series with one rail of saidstretch adjacent oneside of said intersection, a highway crossing signal at said intersection, directional means governed by said two track relays for controlling said signal, and other means connected in series with the other rail adjacent the other side of said intersection for also controlling said signal.

9. In combination, a stretch of railway track including an intersection with a highway, a track circuit including two track relays one connected across the rails at each end of said stretch, a source of track circuit energy connected in series with one rail of said stretch adjacent oneside of said intersection, a highway crossing signal at said intersection, directional means governed by said two track relays for controlling said'signal, another track relay connected in series with the other rail of said stretch adjacent the other side of said intersection, and means governed by saidothertrack relay for controlling said signal.

10. In' combination, a stretch of railway track including anintersection with a highway, a track the other .rail adjacent the other side of said intersection for causing said signal to operate;

. when a trainis occupying the intersection.

11. In combination, a stretchjof railway track including an intersection with a highway, an insulated joint adjacent one side of said'intersec tion separating one rail into a first rail section, and a second rail section, another insulated joint adjacent the other side of saidsection separat ing the other rail into a third rail section and a fourth rail'section, aseries track circuit including a. source of energy and said four rail sections connected in series, a'highway crossi'ng signal at said intersection, and means governed by said scries track circuit for governing said signal.

12. In combination, a stretch of railway track including an intersection with a highway, an insulated joint adjacent one side of said intersection separating one rail into a first rail section and a second rail section, another insulated joint adjacent the other side of said section separating the other rail into a third rail section and a fourth rail section, a series track circuit including a source of energy and said four rail sections connected in series, a highway crossing signal at said intersection, and means including an interlocking relaygoverned by said series track circuit for controlling said signal.

GEORGE R. PFLASTERER. 

